1. Technical Field
The present invention relates to an oscillator, an electronic apparatus, and a base station.
2. Related Art
A crystal oscillator, which is used for a reference frequency signal source for communication equipment, a measurement instrument, or the like, is required to have the output frequency stable with high accuracy with respect to a change in temperature. In general, there is known an oven controlled crystal oscillator (OCXO) as a crystal oscillator capable of providing extremely high frequency stability among crystal oscillators.
In JP-A-2015-041940 (Document 1), there is described an oven controlled crystal oscillator having a first oven, a second oven disposed inside the first oven, a thermosensor for detecting the temperature inside the first oven, a first temperature control circuit for controlling a heater disposed inside the first oven based on the temperature detected by the thermosensor to control the temperature inside the first oven, a first resonator and a second resonator disposed inside the second oven, a frequency difference detection section for detecting a difference in oscillation frequency between the first resonator and the second resonator, and a second temperature control circuit for controlling a heater disposed inside the second oven based on the difference in frequency thus detected to control the temperature inside the second oven.
According to the oscillator described in Document 1, the first resonator and the second resonator are different in frequency characteristics to the temperature, and by arranging that the first temperature control circuit performs the temperature control in a temperature range in which the difference in oscillation frequency between the first resonator and the second resonator with respect to the resonator temperature corresponds one-to-one to each other, it is possible to use double-rotation cut such as SC/IT cut high in frequency stability with respect to the outside air temperature, and thus the temperature characteristics with respect to the frequency can be improved.
However, in the oven controlled oscillator with a plurality of heaters such as the oscillator described in Document 1, there is a possibility that the power consumption increases in particular at the time of startup to exceed the available power consumption.